A 12-member jury in Manhattan federal court on Thursday convicted him on all seven counts he faced after a month-long trial in which prosecutors made the case that he stole $US8 billion ($NZ13.5 billion) from the exchange's customers out of sheer greed.
The verdict came just shy of one year after FTX filed for bankruptcy in a swift corporate meltdown that shocked financial markets and erased his estimated $US26 billion personal fortune.
The jury reached the verdict after just over four hours of deliberations. Bankman-Fried, who had pleaded not guilty to two counts of fraud and five counts of conspiracy, stood facing the jury with his hands clasped in front of him as the verdict was read.
His parents, Stanford Law School professors Joseph Bankman and Barbara Fried, sat in the courtroom's second row, holding each other's hands. Bankman sat with his head in hands after the verdict was read.
The conviction represented a victory for the US Justice Department and Damian Williams, the top federal prosecutor in Manhattan, who made rooting out corruption in financial markets one of his top priorities.
"The crypto industry might be new, the players like Sam Bankman-Fried may be new, but this kind of fraud is as old as time and we have no patience for it," Williams told reporters outside the courthouse.
US District Judge Lewis Kaplan set Bankman-Fried's sentencing for March 28 next year. The Massachusetts Institute of Technology graduate could face decades in prison.
His defence lawyer Mark Cohen said in a statement that he was "disappointed" but respected the jury's decision.
"Mr Bankman Fried maintains his innocence and will continue to vigorously fight the charges against him," he said.
After Kaplan left the courtroom, Cohen put his arm around Bankman-Fried as they spoke at the defence table.
As Bankman-Fried was led out of the courtroom by members of the US Marshals service, he turned around, looked at his parents in the courtroom audience, and nodded. Fried looked toward him and crossed her arms across her chest.
Bankman-Fried is also set to go on trial on a second set of charges brought by prosecutors earlier this year, including for alleged foreign bribery and bank fraud conspiracies.
BANKMAN-FRIED TESTIFIED IN OWN DEFENCE
Once the darling of the crypto world, Bankman-Fried - who was known for his mop of unkempt curly hair and for wearing shorts and T-shirts rather than business attire - instead joins the likes of admitted Ponzi schemer Bernie Madoff, "Wolf of Wall Street" fraudster Jordan Belfort and insider trader Ivan Boesky as notable people convicted of major US financial crimes.
The jury began deliberations on Thursday after hearing the prosecution's rebuttal to the defence closing arguments delivered a day earlier.
Prosecutors argued during the trial that Bankman-Fried siphoned money from FTX to his crypto-focused hedge fund, Alameda Research, despite proclaiming on social media and in television advertisements that the exchange prioritised the safety of customer funds.
Alameda used the money to pay its lenders and to make loans to Bankman-Fried and other executives - who in turn made speculative venture investments and donated upwards of $US100 million to US political campaigns in a bid to promote cryptocurrency legislation the defendant viewed as favourable to his business, according to prosecutors.
Bankman-Fried took the calculated risk of testifying in his own defence over three days near the close of trial after three former members of his inner circle testified against him. He faced aggressive cross-examination by the prosecution, often avoiding direct answers to the most probing questions.
He testified that while he made mistakes running FTX, such as not formulating a risk-management team, he did not steal customer funds. He said he thought Alameda's borrowing from FTX was allowed and did not realise how large its debts had grown until shortly before both companies collapsed.
"We thought that we might be able to build the best product on the market," Bankman-Fried testified. "It turned out basically the opposite of that."
'HE THOUGHT THE RULES DID NOT APPLY'
Prosecutors had a different view.
"He didn't bargain for his three loyal deputies taking that stand and telling you the truth: that he was the one with the plan, the motive and the greed to raid FTX customer deposits - billions and billions of dollars - to give himself money, power, influence. He thought the rules did not apply to him. He thought that he could get away with it," prosecutor Danielle Sassoon told the jury on Thursday.
The jury heard 15 days of testimony. Former Alameda chief executive Caroline Ellison and former FTX executives Gary Wang and Nishad Singh, testifying for the prosecution after entering guilty pleas, said he directed them to commit crimes, including helping Alameda loot FTX and lying to lenders and investors about the companies' finances.
The defence argued the three, who have not yet been sentenced, falsely implicated Bankman-Fried in a bid to win leniency at sentencing.
Prosecutors may ask Kaplan to take their cooperation into account in deciding their punishment.
Bankman-Fried has been jailed since August this year after Kaplan revoked his bail, having concluded he likely tampered with witnesses.
